Plastic fasteners are commonly utilized in the retail industry in a variety of different applications to couple together two or more separate items. For instance, plastic fasteners are often used to couple together (i) a pair of complementary articles of clothing, such as socks, gloves and the like, (ii) a merchandise tag, or ticket, to one or more articles of clothing (e.g., a merchandise ticket folded over the waistline of a pair of jeans), and (iii) a handheld tool, or instrument, to a merchandise display card (e.g., a screwdriver disposed against the front surface of a flat, cardboard display card).
In U.S. Pat. No. 4,039,078 to A. R. Bone, the disclosure of which is incorporated herein by reference, there are disclosed several different types of plastic fasteners. Each plastic fastener described in the patent is manufactured in a generally H-shaped configuration, with two shortened parallel cross-bars, or T-bars, being interconnected at their appropriate midpoints by a thin, flexible filament which extends orthogonally therebetween.
Plastic fasteners of the type described above are commonly fabricated as part of a continuously connected supply of fastener stock, which is also commonly referred to in the art simply as ladder stock due to its ladder-like appearance. Referring now to FIG. 1, there is shown a length of ladder stock that is presently manufactured and sold by Avery Dennison Corporation of Pasadena, Calif. under the PLASTIC STAPLE® and ELASTIC STAPLE® lines of plastic fasteners. As can be seen, a length of ladder stock is shown that is preferably produced from one or more flexible plastic materials, such as nylon, polypropylene and the like, the ladder stock being identified generally by reference numeral 11. Ladder stock 11 comprises a pair of elongated and continuous side members, or rails, 13 and 15 which are interconnected by a plurality of equidistantly spaced cross-links 17.
An individual plastic fastener 18 is obtained from ladder stock 11 by severing side members 13 and 15 at the approximate midpoint between successive cross-links 17. Fastener 18 comprises a pair of cross-bars 19 and 21 which are interconnected by a thin, flexible filament 23, with cross-bars 19 and 21 comprising sections of side members 13 and 15, respectively, and filament comprising a cross-link 17.
Automated plastic fastener dispensing devices, or machines, are well known in the art and are commonly used to dispense individual plastic fasteners from a reel of ladder-type fastener stock.
In U.S. Pat. No. 8,413,866 to W. J. Cooper et al., the disclosure of which is incorporated herein by reference, there is disclosed one well known type of plastic fastener dispensing device that is presently manufactured and sold by Avery Dennison Corporation of Pasadena, California as the ST9500® fastener system, the fastener dispensing device being shown in FIG. 2 and identified generally by reference numeral 30. As can be seen, fastener dispensing device 30 is designed to dispense individual plastic fasteners from a reel of continuously-connected ladder stock 11.
Fastener dispensing device 30 comprises a substantially rectangular base 31 which provides a structural foundation for the machine, base 30 including a plurality of transverse bores 32 at select locations about its periphery through which fastening elements (not shown) can be driven in order to secure device 30 to a workstation or other similar platform. A solid, block-shaped neck 33 is integrally formed onto the top surface of base 31 along its rear edge. In turn, an enlarged, open, rectangular frame 34 is formed on top of neck 33 that serves as a support surface on which various mechanical and electrical components for device 30 are mounted.
An elongated support, or reactor, arm 35 extends out from base 31 and neck 33 in the forward and upward direction, support arm 35 extending beneath the underside of frame 34 in a spaced apart relationship relative thereto. A reactor plate 37 is removably mounted onto the free end of support arm 35 and functions, among other things, to directly support the articles to be coupled by one or more fasteners 18 using device 10, as will be described further below.
A substantially enclosed, protective housing 39 extends upwardly about the periphery of frame 34. Housing 39 is preferably constructed of a rigid, durable and impact-resistant material, such as plastic, and serves to protect the majority of the electrical and mechanical components for device 30 that are mounted on frame 34.
An arcuate recess 41 is formed in the top surface of housing 39. A cylindrical reel holder 43, which is mounted onto housing 39, extends laterally through recess 41 and is dimensioned to pass axially through a longitudinal bore formed in a reel, or spool, 45 around which ladder stock 11 is wound. Accordingly, holder 43 serves to support reel 45 within recess 41 and enable reel 45 to rotate freely during normal operation, thereby rendering device 10 capable of continuously dispensing plastic fasteners in an automated fashion.
Fastener dispensing device 30 comprises a motor-driven head assembly 53 that is mounted on frame 34 along its front end. Head assembly 53 is primarily responsible for dispensing an individual fastener 18 from ladder stock 11. Specifically, head assembly 53 includes a vertically extending mount 55 that is fixedly retained in place on frame 34, mount 55 being generally U-shaped in lateral cross-section. A motor-driven, vertically displaceable head 57 is slidably coupled to mount 55 for purposes to become apparent below.
Head assembly 53 additionally includes a pair of hollow, slotted needles 59-1 and 59-2 that is coupled to vertically displaceable head 57 and is therefore adapted to selectively penetrate through the one or more items to be fastened, a feed mechanism 61 for advancing side members 13 and 15 of ladder stock 11 into axial alignment behind the longitudinal bores defined by needles 59-1 and 59-2, respectively, a severing mechanism 53 for cutting side members 13 and 15 of ladder stock 11 at the approximate midpoint between successive cross-links 17 to separate an individual plastic fastener 18 from the remainder of ladder stock 11, and an ejection mechanism 65 for ejecting cross-bars 19 and 21 of the severed fastener 18 through the bores of the pair of hollowed needles 59 and, in turn, through the one or more items previously penetrated by needles 59.
As referenced briefly above, reactor arm 35 is a narrow support member that terminates beneath the sharpened tips of the pair of needles 59. Reactor plate 37, which is preferably constructed out of steel or another suitably durable material, is removably mounted onto the top surface of reactor arm 35 at its free end. As such, reactor plate 37 is disposed in direct alignment beneath the sharpened tips of the pair of needles 59 prior to activation of machine 30. For aesthetics and ease of operation, the top and side surfaces of reactor plate 37 preferably lie generally flush with the corresponding top and side surfaces of the reactor arm 35 so to create a seamless, integrated, finger-like support surface.
As can be seen, reactor plate 37 is provided with a single, narrow slot 67 that extends the majority of its width. During normal operation of machine 30, slot 67 receives the pair of needles 59 as head 57 is drivers vertically downward, thereby enabling the sharpened tip of each needle 59 to penetrate through the articles supported by reactor plate 37 to a depth sufficient to allow for the subsequent ejection of each cross-bar of a dispensed fastener.
In the above-described embodiment of reactor plate 37, slot 67 extends laterally a significant width in order to (i) accommodate fastener dispensing machines with variable needle spacing (i.e., machines that allow for the spacing between needles to be adjusted) and (ii) allow for slight lateral deflection, or bending, of each needle when penetrating through certain types of materials.
However, fastener dispensing devices of the type described above which include a reactor plate with a single widened slot have been found to suffer from a notable shortcoming. Specifically, due to the inclusion of the widened slot, the reactor plate has been found to inadequately support articles during the fastener dispensing process. In particular, instead of penetrating through the supported articles that are to be fastened, the pair of needles often pushes, or wedges, certain types of materials (e.g., fabric, paper and denim) down into the slot, which is highly undesirable for at least the reasons to he set forth below.
As a first drawback, the inadequate support afforded by reactor plates of the type as described above can cause damage to the articles if pushed too deeply into the lateral slot. Specifically, articles constructed out of relatively delicate materials can become distorted or even torn by the pressure exerted thereon by the pair of needles.
As a second drawback, the inadequate support afforded by reactor plates of the type as descried above often results in the ineffective fastening of articles. More specifically, the inadequate support afforded by reactor plates of the type as described above can result in, inter alia, (i) an increased degree of stress imparted onto the fastener filament during ejection which, in turn, can cause the fastener to break, (ii) an inability of each needle and, as a consequence, each fastener T-end to fully penetrate the article, and (iii) creation of an enlarged hole in the articles by each needle, with the diameter of each hole being too large to retain the 0.1875 inch diameter T-end of a conventional plastic fastener.
In view of the above, it is known in the art for a brush assembly to be coupled to a reactor plate to provide more uniformly distributed article support within the region of the reactor plate through which the needles are designed to selectively penetrate. For example, in U.S. Pat. No. 6,244,490 to S. E. Flannery et al., the disclosure of which is incorporated herein by reference, there is shown a reactor plate assembly which serves as an anvil for a plastic fastener dispensing device, the reactor plate assembly comprising a brush assembly that is mounted on a reactor plate. The reactor plate includes a top surface, a bottom surface and an opening therethrough. The brush assembly includes a high density polyethylene mounting blocking having a top surface, a bottom surface and a recess formed in the top surface. The brush assembly also includes a plurality of nylon brush filaments which are coupled to and extend out from the recess in the mounting block. The brush assembly is mounted on the bottom surface of the reactor plate by screws so that a portion of the plurality of filaments protrudes into the opening in the reactor plate with the free ends of the plurality of filaments lying flush with the op surface of the reactor plate.
Although useful in supporting articles to be fastened, reactor plate assemblies of the type as described above have been found to be unnecessarily large in size and, as a result, are aesthetically unappealing. Specifically, the brush assembly shown in the '490 patent includes an enlarged, square-shaped arrangement of filaments that penetrates through a similarly dimensioned opening in the reactor plate. However, it is to be understood that the surface area of the support region provided by such a brush assembly is unnecessarily large since the pair of needles is only typically designed to move in the lateral direction and therefore does not require a similar range of support in the front-to-back direction. As a consequence, the mounting block for the brush assembly cannot be integrated into the reactor plate in a seamless and inconspicuous manner but, rather, is largely obtrusive in nature.